Unlike traditional chemotherapy, the EV+pembrolizumab combination is producing a "tail on the curve" in survival data. This indicates a significant minority of patients with metastatic bladder cancer are achieving durable, long-term responses—a phenomenon previously unseen and a paradigm shift for the disease.

The transformative efficacy of EV-Pembro has ushered in a new, aggressive treatment philosophy for both muscle-invasive and metastatic bladder cancer. The approach is to administer the combination upfront to gain rapid disease control, and only then make subsequent decisions about surgery, radiation, or further therapy.

The practice-changing Keynote B15 trial showed strong efficacy for neoadjuvant EV-Pembro. However, about half of patients discontinued treatment due to side effects. This creates a clinical paradox: patients who complete the full regimen may be over-treated, while those who stop early due to toxicity may be under-treated, complicating patient management and counseling.

Despite the perception that cisplatin-ineligible patients have worse disease biology, the pathologic complete response rates to neoadjuvant EV Pembro were nearly identical (56-57%) in both cis-ineligible (KEYNOTE-905) and cis-eligible (KEYNOTE-B15) trials. This suggests the regimen's high efficacy may overcome underlying biological differences.

Some oncologists are stopping guideline-supported perioperative treatment regimens early if a patient achieves a pathologic complete response (pCR) from neoadjuvant therapy alone. This practice is considered premature and risky, as data from dedicated de-escalation trials like VOLGA is not yet available to support it.

In cisplatin-ineligible muscle-invasive bladder cancer, neoadjuvant enfortumab vedotin plus pembrolizumab demonstrated a 57% pathologic complete response rate in the KEYNOTE-905 trial. This is an unprecedented result, significantly higher than any previously studied regimen and signals a major shift in perioperative treatment.

New bladder-sparing trials mandate nine cycles of EV-Pembro to replicate the conditions of successful surgical trials. This conservative approach ignores that patient response is front-loaded while toxicity is back-loaded, likely overtreating many patients to ensure comparable efficacy.

Professor Powles predicts a significant shift in bladder cancer treatment. High pathological complete response rates with neoadjuvant EV Pembro may allow responders, identified by imaging and circulating tumor DNA, to safely avoid radical cystectomy, a life-altering surgery that may become unnecessary for many.

With pathologic complete response rates approaching 67% in patients completing neoadjuvant EV-Pembro, a majority of cystectomies are now removing cancer-free bladders. This creates an ethical and clinical imperative to rapidly launch prospective trials to validate bladder preservation strategies and avoid overtreatment.